Macro partitioning
Protein supplementation significantly enhances muscle strength and fat-free mass gains during arduous concurrent training, but does not improve aerobic endurance.
If you are doing both weightlifting and cardio (like military training or CrossFit), take 20-50g of protein immediately after your workout. This will help you build more muscle and lose fat faster than if you didn't supplement. However, do not expect this to improve your running or cycling endurance; for that, focus on your aerobic training volume.
protein supplementation improved performance outcomes in response to concurrent training (ES = 0.89, 95% CI = 0.08–1.70). When analysed separately, improvements in muscle strength (SMD = +4.92 kg, 95% CI = −2.70–12.54 kg) were found, but not in aerobic endurance. Gains in fat-free mass (SMD = +0.75 kg, 95% CI = 0.44–1.06 kg) and reductions in fat-mass (SMD = −0.99, 95% CI = −1.43–0.23 kg) were greater with protein supplementation.
Why this rating
Systematic review and meta-analysis of 11 studies, though with substantial heterogeneity (I2 > 90%) and potential publication bias.
Source
Does Protein Supplementation Support Adaptations to Arduous Concurrent Exercise Training? A Systematic Review and Meta-Analysis with Military Based Applications
Shaun Chapman et al. · Nutrients · 2021
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